Arizona is deploying 225 National Guard troops to support President Trump’s call for the military to help secure the U.S.-Mexico border, its governor announced Monday.

“Just updated Arizona border sheriffs on today’s deployment of National Guard. LATEST: 225 guard members being deployed today, additional members tomorrow,” Arizona Gov. Doug Ducey (R) said in a tweet.

“These troops will be helping our federal partners with any support role responsibilities that they need, and will be stationed in both the Tucson and Yuma sectors,” he added in a second tweet.

Just updated Arizona border sheriffs on today’s deployment of National Guard. LATEST: 225 guard members being deployed today, additional members tomorrow. pic.twitter.com/HL4lATRyNX

— Doug Ducey (@dougducey) April 9, 2018

These troops will be helping our federal partners with any support role responsibilities that they need, and will be stationed in both the Tucson and Yuma sectors. https://t.co/5qB2kiV1RP

— Doug Ducey (@dougducey) April 9, 2018

Trump first announced last week that he wanted to deploy U.S. troops to guard the southern border until his proposed wall is built.

{mosads}Trump then signed an order Wednesday night to deploy National Guard troops to the border.

Defense Secretary James Mattis followed that up by issuing a memo Friday night that authorized up to 4,000 National Guard troops to support the Department of Homeland Security’s (DHS) border security mission.

Mattis’s memo stipulates that the guardsmen are not to perform law enforcement activities or interact with migrants or other individuals detained by DHS without his approval. The troops will be armed only if it’s required for self defense, the memo adds.

“Together, the Departments of Homeland Security and Defense are committed to using every lever of power to support the men and women of law enforcement defending our nation’s sovereignty and protecting the American people,” Mattis and Homeland Security Secretary Kirstjen Nielsen said in a joint statement Friday. “We will continue to work with the governors to deploy the necessary resources until our nation’s borders are secure.”

Arizona’s Guard troops join the 250 that Texas’s governor announced Friday he would send.

New Mexico Gov. Susana Martinez (R) has said her state would participate in the operation, but has not announced a specific deployment. California Gov. Jerry Brown (D) has not said if his state’s Guard members will participate.

Critics have questioned whether the Guard deployments are necessary or are taking away dollars that the Pentagon has said is needed to fix an urgent readiness crisis.

Former President George W. Bush sent about 6,000 Guard troops to the border in 2006, while former President Obama sent about 1,200 guardsmen to the border in 2010. The deployments together were estimated to cost about $1.3 billion, according to the Government Accountability Office.